Electrical power may be transmitted from a source to a point of use through an electrical distribution system within a home or a commercial building for equipment and operations. Conventional electrical receptacles within such a distribution system generally include a cover having one or more sockets, a body to which the cover is secured to provide a housing for internal conductive terminals corresponding to respective Hot (phase) and Neutral of an alternating current power source and each situated in respective alignment with respective blade openings formed in the sockets of the cover for receiving corresponding blades, including polarized blades, of an electrical plug. The receptacle may also include an electrical ground terminal within the body in alignment with a pin opening formed in each respective socket for receiving a corresponding ground pin of the electrical plug. For example, the receptacle may include a strap sub-assembly. The strap may include structures, e.g., slots, pins, etc., that permit the receptacle to be mounted to threaded mounting holes of a standard outlet box. The strap may be affixed to the body by a center pin shaft and pin or mounting screw that additionally affixes the cover to the body. A bushing for a mounting screw is provided for securing the body to the cover.
Further, since a large percentage of these receptacles are used in residential buildings and are located near the floor, it may be beneficial to provide added protection when a young child or infant may come into contact with the receptacle. For example, a small object inserted into either one of the apertures potentially may result in electrical shock.
Children may insert into receptacles a wide variety of objects made of conductive material including but not limited to metal articles. Most objects may be everyday household and easily accessible items such as paper clips, pens, wire tools, hairpins, safety pins, keys, forks, knives, screws, nails, tweezers and coins.
Both scenarios present circumstances to be avoided, where possible. As such, the issue of human safety and avoiding hazards has always been considered by the owner of the instant application in developing new products. Further, in an effort to eliminate the foregoing, the National Electrical Code (NEC) now requires tamper-proof electrical receptacles in pediatric environments. A National Electrical Manufacturer's Association (NEMA) task force has concluded that every residential building should be required to have tamper-resistant (TR) electrical receptacles within the electrical distribution system throughout the home.
As a result, it is known in the art to incorporate a TR mechanism to prevent improper use of the electrical receptacle. Generally speaking, the use of TR mechanisms has become wide spread. TR mechanisms provide a simple and effective mechanism that does not need continuous manual adjustment. TR mechanisms prevent electric shock when one inserts an object into one aperture in the cover, while still permitting the frequent insertion and removal of plugs to an electrical appliance.
Furthermore, in recent times, as the use of three prong receptacles including a Hot (phase) blade opening, a Neutral blade opening and a ground pin opening formed in the cover for receiving corresponding blades of an electrical plug, it would be beneficial to provide a TR mechanism that prevents the insertion of two bladed plugs that do not include a ground pin.
Thus, it would be desirable to provide a TR mechanism that prevents the insertion of a conductive material into a single blade opening while also preventing the insertion of a two bladed plug into a three prong receptacle.